Method and Apparatus for Supporting Reauthentication of Dn Authorized Pdu Session and Managing Pdu Session According to Change of Dn Authorization Data

1. A method performed by a first network entity performing a session management function (SMF) in a communication system, the method comprising: identifying an initiation of a re-authentication for a protocol data unit (PDU) session; receiving, from a second network entity performing a data network (DN) authentication, authorization and accounting (DN-AAA), a DN authorization profile index for the PDU session, during the re-authentication; and transmitting, to a third network entity performing a policy control function (PCF), the received DN authorization profile index, in case that the received DN authorization profile index has changed from a DN authorization profile index associated with an authentication for the PDU session.

2. The method of claim 1 , further comprising: receiving, from the third network entity, policy information for the PDU session; and applying the policy information for the PDU session.

3. The method of claim 1 , further comprising: transmitting, to a terminal associated with the PDU session, an extensible authentication protocol (EAP) success message notifying a success of the re-authentication.

4. The method of claim 1 , wherein the re-authentication is a secondary re-authentication for the PDU session.

5. The method of claim 1 , wherein the re-authentication for the PDU session is initiated by the first network entity or the second network entity.

6. A method performed by a second network entity performing a data network (DN) authentication, authorization and accounting (DN-AAA) in a communication system, the method comprising: identifying an initiation of a re-authentication for a protocol data unit (PDU) session; and transmitting, to a first network entity performing a session management function (SMF), a DN authorization profile index for the PDU session, during the re-authentication, wherein the DN authorization profile index is transmitted from the first network entity to a third network entity performing a policy control function (PCF), in case that the transmitted DN authorization profile index has changed from a DN authorization profile index associated with an authentication for the PDU session.

7. The method of claim 6 , wherein policy information for the PDU session is transmitted from the third network entity to the first network entity, and wherein the policy information is applied by the first network entity for the PDU session.

8. The method of claim 6 , wherein an extensible authentication protocol (EAP) success message notifying a success of the re-authentication is transmitted from the first network entity to a terminal associated with the PDU session.

9. The method of claim 6 , wherein the re-authentication is a secondary re-authentication for the PDU session.

10. The method of claim 6 , wherein the re-authentication for the PDU session is initiated by the first network entity or the second network entity.

11. A first network entity performing a session management function (SMF) in a communication system, the first network entity comprising: a transceiver; and a controller configured to: identify an initiation of a re-authentication for a protocol data unit (PDU) session, receive, from a second network entity performing a data network (DN) authentication, authorization and accounting (DN-AAA) via the transceiver, a DN authorization profile index for the PDU session, during the re-authentication, and transmit, to a third network entity performing a policy control function (PCF) via the transceiver, the received DN authorization profile index, in case that the received DN authorization profile index has changed from a DN authorization profile index associated with an authentication for the PDU session.

12. The first network entity of claim 11 , wherein the controller is further configured to: receive, from the third network entity via the transceiver, policy information for the PDU session, and apply the policy information for the PDU session.

13. The first network entity of claim 11 , wherein the controller is further configured to: transmit, to a terminal associated with the PDU session, an extensible authentication protocol (EAP) success message notifying a success of the re-authentication.

14. The first network entity of claim 11 , wherein the re-authentication is a secondary re-authentication for the PDU session.

15. The first network entity of claim 11 , wherein the re-authentication for the PDU session is initiated by the first network entity or the second network entity.

16. A second network entity performing a data network (DN) authentication, authorization and accounting (DN-AAA) in a communication system, the second network entity comprising: a transceiver; and a controller configured to: identify an initiation of a re-authentication for a protocol data unit (PDU) session, and transmit, to a first network entity performing a session management function (SMF) via the transceiver, a DN authorization profile index for the PDU session, during the re-authentication, wherein the DN authorization profile index is transmitted from the first network entity to a third network entity performing a policy control function (PCF), in case that the transmitted DN authorization profile index has changed from a DN authorization profile index associated with an authentication for the PDU session.

17. The second network entity of claim 16 , wherein policy information for the PDU session is transmitted from the third network entity to the first network entity, and wherein the policy information is applied by the first network entity for the PDU session.

18. The second network entity of claim 16 , wherein an extensible authentication protocol (EAP) success message notifying a success of the re-authentication is transmitted from the first network entity to a terminal associated with the PDU session.

19. The second network entity of claim 16 , wherein the re-authentication is a secondary re-authentication for the PDU session.

20. The second network entity of claim 16 , wherein the re-authentication for the PDU session is initiated by the first network entity or the second network entity.

21. The method of claim 10 , further comprising: transmitting, to the first network entity, a message for requesting the re-authentication, based on the re-authentication for the PDU session being initiated by the second network entity.

22. The second network entity of claim 20 , wherein the controller is further configured to: transmit, to the first network entity, a message for requesting the re-authentication, based on the re-authentication for the PDU session being initiated by the second network entity.